Process of manufacturing flexible cellulosic products



, struct the'wire gauze.

Patented May 16, 1944 PROCESS OF MANUFACTURING FLEXIBLE CELLULOSICPRODUCTS Gaston Hubert Vulliet-Durand, Paris, France;

vested inthe Alien N Drawing.

Property Custodian Application March 10, 1939, Serial No. 261,154. InFrance March 10, 1938' 1 Claim.

The present invention relates to a new plastic sheet material and theprocess for making the same. The invention is particularly applicable topaper and pasteboard products.

One of the objects of the present invention is to provide anew'cellulose pulp product of high flexibility, great strength, and goodwearing quality. A further object of the invention is to provide a newuse for mannan meal, a by-prodnet of the manufacture of buttons fromivory nuts.

Ordinarily; in the paper and pasteboard industries, it is not possibletouse substances which form gelatinous aggregates in the presence of waterbecause such jellylike aggregates prevent proper drainage in the papermachine and ob- In the process of the present invention, mannan is usedas a gelatinizing substance and the product of the present invention itcharacterized in that it contains a large proportion of mannan mixedwith paper pulp.

According to the present invention, mannan meal is treated with areagent to alter its properties and to give a product, insolubilizedmannan, which when mixed with cellulose pulp may be readily formed intosheets. The sheet is then dried ndvplaced in a gelatinizing bath, afterwhich, 11 is dried. The result- 'efinished product ing product isflexible and very strong with respect to wear and tear and therefore iscapable of extensive use,

The insolubilized" mannan may be prepared by treatment of mannan mealwith a base, alkaline carbonate, lead salt, .basic copper or similarreagent prior to its introduction into the cellulose pulp. The inventionmay be more particularly understood from the following examples:

Example 1 by ventilation. The mannan meal thus obtained is transferredto a heater and mixed with water and cellulose pulp in the proportionsof 100 pounds cellulose pulp, 100 pounds insoluble mannan and 56 poundssoluble mannan. The result- Example 2 Two hundred pounds of mannan mealare heated in a water bath with 45 pounds of potassium or sodiumcarbonate and suflicient water to dissolve the carbonate, after which aprecipitation agent for the pseudosolution of mannan is added. Anyprecipitation or jellification agent of the pseudosolution of mannan canbe employed as for example, alcohol or acetone. The whole mixture isthen transferred to a centrifugal drying machine and, after washing thetreated mannan is transferred to a beater and mixed with cellulose pulpas in Example 1. The product thus obtained is converted on a papermachine to sheets or other shapes and dried in known manner by a pressor a centrifugal machine, after which it is kept in a bath forgelatinizing the mannan. Satisfactory results may be obtained by usingacidulated water, aqueous glycerine, or formaldehyde in the gelatinizingbath. The finished plastic sheet is obtained after a final drying.

The foregoing description has been given by way of example only and thedetails may be varied without departing from the principle and scope ofthe invention.

Having thus described my invention, what I claim is:

The process for the production of a flexible cellulose pulp productwhich comprises solubilizing mannan by heating with a solution of-sodiumcarbonate, precipitating the mannan with alcohol,

mixing the precipitated mannan with cellulose Pulp. giving the mixturethe desired form, drying the formed material, soaking the form in a bathof acidulated water and finally drying.

GASTON nosrza'r Walteranama.

